The present invention relates to a process of producing ethyl alcohol (ethanol), and more particularly to such a process where ethyl chloride, hydrogen chloride, perchloroethylene and oxygen are reacted in the presence of a catalyst, using ethane as a diluent, to yield reaction products comprising ethyl alcohol and hexachloroethane, and wherein the hexachloroethane is reacted with ethane to produce the ethyl chloride, hydrogen chloride, and perchloroethylene reactants for the ethyl alcohol and hexachloroethane producing reaction.
Ethyl alcohol is a chemical compound having a multitude of industrial and commercial applications, including as a precursor in the production of numerous organic chemicals such as ether, butadiene, chloroform, as well as in the production of beverage alcohols, and as a fuel for internal combustion engines.
Ethanol is conventionally manufactured for industrial uses by one of the following two methodologies. According to the first method, ethtylene is hydrolyzed under various conditions to form ethyl alcohol. Per the second method, which dates back centuries, ethyl alcohol is produced by the fermentation of sugar with yeast. Ethanol used for alcoholic beverages is produced almost exclusively by this fermentation process. Although practiced on a large scale, both of the foregoing methods suffer drawbacks, including relatively high production costs. For example, ethylene, the ethanol precursor in the first method, is an expensive compound.
As disclosed in U.S. Pat. No. 5,185,479, issued to the named inventor hereof, it is known to produce methyl alcohol (methanol) by reacting perchloroethylene and methyl chloride with hydrogen chloride and air. This process, however, is attended by several operational drawbacks. When air is employed for oxychlorination, a substantial quantity of gases must be vented, thereby complicating emission control problems and related environmental concerns. On the other hand, the use of pure oxygen, as has been discovered by the inventor hereof, complicates the oxychlorination reaction due to the formation of hot spots on the catalyst. A further drawback is the need to employ an absorber/stripper facility in order to separate methane from hydrogen chloride in the effluent from the chlorination or thermal reactor. This requirement impacts the energy efficiency of the process, and further increases the capital investment necessary to produce methanol by this methodology.
There consequently exists a need for a process of manufacturing ethanol which is at once economical and reduces the inefficiencies characterizing conventional processes.
The specification discloses a largely self-contained process for producing ethyl alcohol, comprising the following reaction steps, operated in tandem:
A first reaction step wherein ethyl chloride, hydrogen chloride, perchloroethylene and oxygen are reacted in the presence of a catalyst, using ethane as a diluent, to yield reaction products comprising ethyl alcohol and hexachloroethane; and a second reaction step wherein the hexachloroethane of the first reaction step is reacted with ethane to produce ethyl chloride, hydrogen chloride, and perchloroethylene, which products are supplied as reactants to the first reaction step, along with any unreacted ethane. Substantially all of the oxygen and hydrogen chloride reactants in the first reaction step are consumed, thereby doing away with the need for an absorber/stripper facility.
Per another feature of this process, the catalyst of the first reaction step comprises copper chloride or an admixture of copper chloride and a salt selected from the group consisting of potassium chloride, iron chloride, cesium chloride, zinc chloride, lead chloride, and bismuth chloride.
According to another feature of the invention, the first reaction step is carried out at a temperature in the range of from approximately 200xc2x0 Centigrade to approximately 375xc2x0 Centigrade.
Per another feature, the first reaction step is carried out at a pressure in the range of from approximately 2 atm. to approximately 10 atm.
Per still another feature, the second reaction step is carried out at a temperature in the range of from approximately 400xc2x0 Centigrade to approximately 700xc2x0 Centigrade.